Apparatus for truing face mill cutters



July 4, 1933. s. H. EARL 1,917,103

APPARATUS FORTRUI NG FACE MILL CUTTERS Filed April 15, 1929 r 2 Sheets-Sheet l FIGZ INVENTOR SCHUYLER H. EARL ATTORNEY July 4; 1933. s EARL I 1,917,103

APPARATUS FOR TRUING FACE MILL CUTTERS FiledAp'ril 15, 1929 ZShee'ts-Sheet 2 INVENTOR A SCHUYLER H. EAR

FIGA BY Patented 4,; I

J n l eatibja filed April Q15,

71 if Thei feeent iniienti n idetee'te tli t'ruingj "*l f of inserted blzide cntt rerand in paiitic'nlan to" wthe tru ing' t dptlble 'end'ied fbladetfiacekmill-- geaifcutters.

wlnventibnchask its g'purp os ,geai' cutters together withf asimple;inezqjenf g Fieuegi with the-cutter removed v I ended face mill cutters ha ve'trecently come i Figure 1 s ,,.slde e'lekzafionof wage-1 1 cutter having double-stifledcuttingblades t this cutterpcsiticneclacn a tnuingfiXtu 20 I 01 thezpn rpo se the blades sive and quickly;manipuleble. fixture for can nyingputthes truing niethd. 1 ""if.

Oftl ei featuresgf nth invention ill appear from the fellowdng-descitiption W-he maid conjunction Withfthe lclna wings andpw illiv-jbe' pqinted but infzthe appended ,In thgtlxjaviimg'slfl EiguneQis:arsidekelevatienal'viewShe p v sti'ticte d f according to the present inventing:

, Viewv ofthe trying Iggtune eplan cutter and fixture shown in" Figqre 2, thei Figure?) .isayiewrofa detail ofgthe t ping fi'xtufe, showing in Section the height ring; As thegeic les ofvtheblac le o f a lftce millgear cutter converge; 'in .;i-cccrdance' with the r surefangl'e and number cf the .cflttflgtbwfirdf t-hetip icf theiblade, it seen .thatfitjis Very 'esenti ahto'set :thebjlades in 'e jcl itterf sei that' all extend thegs arne distance: from 7 be'fclitting na ri e wer and others idengno'ovesrinthe gea rxblank.

' The 'pzgesent invention hileapplicabie to the truing "up "05f all ty-pes of niece ,mill g eart I cutters is especially. (adapted to the tnuing into. Inse particularly for the foughln 'ofl area-secured in the jeqn i rotatable cutter hear tirilg w nsk rbe 7 I Emmet wmmw: M111 1 "a igle fq'ffi-elie-fof the-"tipfdces 1 the cutting blades" dmble hw w 1 1192b, "Serial no 355,357.

canjbeinverftedfend for'jend tonseeitheriends oi (the. blades. The blades '-Of-- these, icl'itte'fs ate nl'idje, withlotl'tshoulders sd that theyeainh ,beadjustedlaxiall'yofthecutterheadltoeet' c The.jcutter to be'tlfuedisfcenteredion e iheidggthereon ,against' axm The cutterhead' zthenfrotated li htly e 2111 {at the s amt? distance omens will all g-extendthefisiairrie. -"d-isaiebjth "a I with cutting; portionsfat tzbqth Thebla'desfshdwnjthi'drztfivings o i d type; 1 M3 5 hey 9O 1 2finrlicatesthe cuttingpccption v a vt c'ne 4 h df tbl d an'dfrl fth m-111 v the othei endj'cif the ibladesI "Gutti'ng pdrtionsare elieved 1 side and top cutting fleflges f to,

H-YEARL! L R E E MW Y RK;teemTweet t e y -i rm d @ndiwop ut ing clearance; ,AsWiHb e seeninfrthedrawings;

:encjls'v ,cffithe .lbl afdesf are ,Loppos'ijtely' 'thsi't is, the cutting'poftions lat-e 10p; 1

dl ilrecteii li at the two -ende cdf the 19 I blades. They are so constructedin order to permit inverting the cutter end for end on the spindle of a gear cutting machine to use either end of the cutter for cutting a gear. It

is not necessary to invert the individual in a direction parallel to the axis of the cutter head and the blades 11 are secured in these slots. The blades are held in position on the cutter heads by the bolts 16 and washers 17. The holes 18 in the cutter blades 11 through which the bolts 16 pass are made of slightly greater diameter than the diameter of the bolt stems so that the blades can be adjusted slightly on the cutter head in an axial direction to permit of the truing opi eration as will be hereinafter described.

By the use of shims 20 of various sizes, slight .changes in the diameters of the cutters can be made. i

The cutter truing fixture comprises a generally circular base that is formed on its upper face'with a circular flange or seat 26 which is disposed centrally ofthe base. The center part of the base is recessed from the top as indicated at 27 and provided with a screw threaded opening below this recess. 29 designates a post or stud. This post or stud 29 is provided with a tapered collar 30, the lower face of which rests on the flange 26. Below the collar 80, the stud 29 is of reduced diameter and is provided with a second cylindrical collar 31-.which fits in the circular recess 27 of the base and centers the stud in the base. The lower end of the stud below the collar 31 is threaded and 7 screws into the threaded opening formed in the base 25 to assemble the stud on the base. Seatedon the upper face of the base 25 and surrounding the flange 26 is a hardened steel disc 32 which is formed-with two spaced circular seats 34 and 35, the upper faces of which lie in the same horizontal plane. This disc 32 is secured to the base by the screws 33. The seats 342 and 35 serve asa rest for thecutterjto be trued and the cutter is cen- 39 tiered on thebase by the collar 30 of the stud 29 which is adapted to enter the taper at, either end of the bore of the cutter.

The base 25 is formed in a horizontal plane below its top face with an annular seat on which the ring 40 is secured, as by means of the screws 39. This ring 40 is of a diameter correspondingto the diameter of the out ter to be trued. It is formed on its upper face with a plurality of seats 41, the upper-most points ofwhich all lie in the same horizontal plane. The top faces of the seats are inclined to this horizontal plane at an angle corresponding to the relief angle of the tips of the cutter blades. The seats correspond in number, of course, to the number of blades in the cutter and the ring 40 may be grooved or notched. between the successive seats as indicated at 42.

The stud 29 is of reduced diameter atits upper end as indicated at 4:5 in Figure 4E. Surrounding this part of the stud and resting on the shoulder formed thereby is a coiled spring 46. 47 designates a removable clamping disc that serves to hold the cutter to be trued on the truing fixture and 4.8 designates a lock washer which servesto secure the clamping disc 47 in position. The lock washer 48 is provided with'three lugs or fingers disposed at 120 to each other and the clamping disc 47 is provided with three slots disposed at 120 apart which areshaped to correspond to the shape of the lugs of the lock washer with the consequence that when the clamping disc is rotated so that its slots align with the lugs of the loclrwasher, the clamping disc can be removed from the fixture by sliding it over the lock washer; While when the clamping disc is rotated so that its slots are out of alignment with the lugs of the lock washer, the clamping disc will be held in position to hold the cutteron the truing fixture. the upper end of the reduced portion 45 of the stud 29 can be threaded up to force the clamping disc 47 into engagement with the cutter to be trued to secure the cutter against rotation on the fixture. The coil springdti serves to move the lock washer l8 upwardly.

when the nut 49' is unthreaded so as to release the clamping pressure on the clamping disc 47.

The clamping disc 47 may be formed with three finger grips 50, 120 apart to permit the operator to readily lift the clamping disc oil" of the fixture or put it on the same. A removable wrench 51 is provided for manipulating the nut 49. i

In truing cutters with the device illustrated, one of the blades is first fixed in the cutter head as to height, in other words, so that the cutting portions or portion extend or extends the correct distance from the face ofthe cutter head. Thismay be done in any way or by the use of any suitable or convenient means. In the case of doubleended roughing cutter blades, it is quite easy for the operator to center one blade with reference to the bolt 16 by eye and then secure it in position.

l/Vith the other blades loosely heldto the head by the bolts 16, the cutter head is placed on the truing fixture, the clamping disc 17 and wrench 51 having been first removed. The disc 32 serves to locate the cutter in true horizontal plane and the collar 30 serves A. nut 49 which is threaded on to 

